&#34;secured&#34; fiber optic connecting system and method using different fiber positions of a multi-fiber connector

ABSTRACT

Provided is a multi-fiber connector and a method of providing a secure fiber network, where the multi-fiber connector includes a housing; a multi-position ferrule disposed within the housing, the multi-position ferrule including a plurality of fiber holes arranged in a predetermined pattern; and at least one fiber. Each of the plurality of fiber holes is configured to receive one of the at least one fiber and each fiber is selectively inserted within one of the plurality of fiber holes at a selected position among the plurality of fiber holes. Additionally, only a portion of the plurality of fiber holes are populated with the at least one fiber and a remaining portion of the plurality of fiber holes are not populated with fibers.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of application Ser. No. 12/746,050 filed Jun. 3,2010, which is a national stage of PCT/US2009/067720 filed Dec. 11,2009, which claims priority from U.S. Provisional Application61/121,733, filed on Dec. 11, 2008, the disclosure of which isincorporated herein by reference in its entirety.

BACKGROUND

1. Field

Apparatuses and methods consistent with the exemplary embodiments relateto a security connecting system, and more particularly, to a securityconnecting system for providing interconnection between a single pair ormultiple pairs of mating optical fibers.

2. Description of the Related Art

Optical fibers find extensive use for transmission of light for digitalcommunications by modulating light signals to convey data orinformation. The fibers are fragile and have extremely small diameters.Typically, the optical fibers are coupled to a light transmitting deviceat one end, and light receiving device at the other end. The ends of thefibers may also be coupled in an end-to-end relationship with othermating fibers, and at times multiple optical fibers must besimultaneously coupled. In order to provide reliable coupling and ensurehigh efficiency in the transfer of light or light signals, it iscritical that the ends of the optical fibers be precisely aligned withthe ends of other fibers or devices to which they are coupled.

Ferrules are used to provide a mechanically robust mount within aconnector for holding optical fibers in a desired position. The ferruleis usually a rigid tube or housing that aligns and protects the strippedend of a fiber. The ferrule may have a one or multiple fiber holes whichextend in a through the longitudinal axis of the ferrule and a singlefiber is passed through each fiber hole. Such ferrules may be made ofmetal, plastic glass or ceramic.

There is an increasing need for physical security and identification ina network. One method in the related art is to create physical “keying”features on a connector housing to prevent connection into an adapterunless the adapter too has the complementary “keying” feature. Forexample, a secured connecting system of the related art may use physicalbarriers to prevent unauthorized insertion of a connector plug into aconnector receptacle in an adapter.

Another secured connecting system of the related art may use physicalbarriers to prevent unauthorized removal of a connector plug that isalready connected to the adapter.

In both cases, the secured connecting systems of the related art requiredifferent connector housings with different physical barriers to preventeither unauthorized insertion of a connector plug into the receptacle ofan adapter or unauthorized removal of a connector plug from the adapter.

Thus, a security connecting system which eliminates the need to createmultiple types of connector housings and adapters to establish physicalsecurity in connecting system of a network is needed.

SUMMARY

According to an aspect of an exemplary embodiment, there is provided amulti-fiber connector including a housing; a multi-position ferruledisposed within the housing, the multi-position ferrule including aplurality of fiber holes arranged in a predetermined pattern; and atleast one optical fiber. Each of the plurality of fiber holes isconfigured to receive one of the at least one optical fiber and eachoptical fiber is selectively inserted within one of the plurality offiber holes at a selected position among the plurality of fiber holes.To create security in an inter-connection between multi-fiberconnectors, only a portion of the plurality of fiber holes are populatedwith the at least one optical fiber and a remaining portion of theplurality of fiber holes are not populated with fibers.

The multi-fiber connector may include only one optical fiber.Alternatively, the multi-fiber connector may include at least twooptical fibers. However, at least one of the plurality of fiber holes isnot populated with the at least one optical fiber.

According to an aspect of another exemplary embodiment, there isprovided a multi-fiber connector system including a first multi-fiberconnector and a second multi-fiber connector.

The first multi-fiber connector includes a housing; a multi-positionferrule disposed within the housing, the multi-position ferruleincluding a plurality of fiber holes arranged in a predeterminedpattern; and at least one optical fiber. Each of the plurality of fiberholes is configured to receive one of the at least one optical fiber andeach optical fiber is selectively inserted within one of the pluralityof fiber holes at a selected position among the plurality of fiberholes. In addition, only a portion of the plurality of fiber holes arepopulated with the at least one optical fiber and a remaining portion ofthe plurality of fiber holes are not populated with fibers.

The second multi-fiber connector includes a housing; a multi-positionferrule disposed within the housing, the multi-position ferruleincluding a plurality of fiber holes arranged in a predetermined patternhaving matching positions corresponding to the predetermined pattern ofthe first multi-fiber connector; and at least one optical fiber. Each ofthe plurality of fiber holes is configured to receive one of the atleast one optical fiber and each optical fiber is selectively insertedwithin one of the plurality of fiber holes at a selected position amongthe plurality of fiber holes. The plurality of fiber holes of the secondmulti-fiber connector are populated with the at least one optical fibersuch that the first multi-fiber connector and the second multi-fiberconnector have a matching configuration of populated fiber holes andunpopulated fiber holes.

The multi-fiber connector system may also include an adapter whichincludes a first receptacle configured to receive the first multi-fiberconnector and a second receptacle configured to receive the secondmulti-fiber connector, such that the at least one optical fiber of thefirst multi-fiber connector and the at least one optical fiber of thesecond multi-fiber connector mate in coaxial alignment to effect aninterconnection.

According to an aspect of another exemplary embodiment, there isprovided a method of connecting multi-fiber connectors in a secure fiberoptic network, the method includes selecting at least one fiber hole ofa plurality of fiber holes of a first multi-fiber connector to populatewith an optical fiber; selecting not to populate at least one fiber holeof the plurality of fiber holes of the first multi-fiber connector withanother optical fiber such that only a portion of the plurality of fiberholes of the first multi-fiber connector are populated with at least oneoptical fiber and a remaining portion of the plurality of fiber holes ofthe first multi-fiber connector are not populated; inserting the atleast one optical fiber in only the selected at least one fiber hole ofthe first multi-fiber connector; selecting at least one fiber hole of aplurality of fiber holes of a second multi-fiber connector to populatewith another optical fiber; selecting not to populate at least one fiberhole of the plurality of fiber holes of the second multi-fiber connectorwith another optical fiber such that only a portion of the plurality offiber holes of the second multi-fiber connector are populated withanother at least one optical fiber and a remaining portion of theplurality of fiber holes of the second multi-fiber connector are notpopulated, inserting the another at least one optical fiber in only theselected at least one fiber hole of the second multi-fiber connector;inserting the first multi-fiber connector into a first receptacle of anadapter; and inserting the second multi-fiber connector into a secondreceptacle of the adapter such that the at least one optical fiber ofthe first multi-fiber connector and the another at least one opticalfiber of the second multi-fiber connector mate in coaxial alignment toeffect an interconnection. When a proper connection is formed, the firstmulti-fiber connector and the second multi-fiber connector have amatching configuration of populated fiber holes and unpopulated fiberholes.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects will become apparent and more readilyappreciated from the following description of the exemplary embodiments,taken in conjunction with the accompanying drawings, in which:

FIG. 1A illustrates a multi-position ferrule of a multi-fiber connectoraccording to an exemplary embodiment of the present invention.

FIG. 1B illustrates a multi-position ferrule of a multi-fiber connectoraccording to another exemplary embodiment of the present invention.

FIG. 2 illustrates a connecting system according to an exemplaryembodiment of the present invention.

FIG. 3 shows matching fiber positions in a pair of connector plugs,mating in a key-up-to-key-up configuration according to anotherexemplary embodiment.

FIG. 4 shows two pairs of matching fiber positions in a pair ofconnector plugs, mating in a key-up-to-key-down configuration accordingto another exemplary embodiment.

FIG. 5 shows two pairs of matching fiber positions in a pair ofconnector plugs, mating in a key-up-to-key-up configuration according toanother exemplary embodiment.

FIG. 6 shows matching fiber positions in a pair of connector plugs withtwo rows of possible fiber positions, mating in a key-up-to-key-downconfiguration according to another exemplary embodiment.

FIG. 7 shows matching fiber positions in a pair of connector plugs withtwo rows of possible fiber positions, mating in a key-up-to-key-upconfiguration according to another exemplary embodiment.

FIG. 8 shows two pairs of matching fiber positions in a pair ofconnector plugs, mating in a key-up-to-key-down configuration accordingto another exemplary embodiment.

FIG. 9 shows two pairs of matching fiber positions in a pair ofconnector plugs, mating in a key-up-to-key-up configuration according toanother exemplary embodiment.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments will be described in detail with reference toaccompanying drawings so as to be easily realized by a person havingordinary knowledge in the art. The inventive concept may be embodied invarious forms without being limited to the exemplary embodiments setforth herein. Descriptions of well-known parts may be omitted forclarity, and like reference numerals refer to like elements throughout.

Fiber optic connectors typically interconnect a pair of optical fibersaligned in an end-to-end disposition to provide optical transmissiontherebetween. In a multi-fiber connector, two or more optical fibers maybe contained within a single jacket. To interconnect such a multi-fiberoptical cable, each fiber within the multi-fiber optical cable issecured to a respective connector. When multiple pairs of fiber opticconnectors are to be connected, the fiber optic connectors requiremutual alignment of respective fiber cores in a repeatable, separableinterconnect.

According to an exemplary embodiment of the present invention, a ferruleis used together with the connector that connects the fiber cable eitherto another cable, to a transmitter or to a receiver. The ferrule keepsthe optical fibers in a fixed position and accurately aligned within theconnector. For example, an optical fiber may be inserted into a fiberhole of the ferrule, and fixed thereto by an adhesive. Additionaloptical fibers may be inserted into one of the remaining available fiberholes.

An end face of the optical fibers may be finished to be flush with orslightly protruding from an end face of the ferrule. The optical fibersheld by the ferrule, particularly the fiber end faces, may be polishedwith a minor finish. When complimentary ferrules are adjoined, typicallyin an abutting relationship, two optical fibers mate in coaxialalignment to effect an interconnection. Accordingly, optically encodedinformation carried in the core of the optical fibers can be transmittedtherebetween.

A Mechanical Transfer (MT) ferrule is one type of multi-fiber ferrule,and may be used to simultaneously connect multiple optical fibers usingmultiple fiber holes. Each fiber hole receives one optical fiber andfiber alignment is dependent on the arrangement of the fiber holes. Thearrangement of the fiber holes can made in various patterns which mayinclude two or more fiber holes. The arrangement of the fiber holes mayalso vary according to a pitch between holes and a hole diameter,however, the exemplary embodiments are not limited to any particulararrangement so long as two mating ferrules have a matching arrangement.

FIG. 1A illustrates a 12-hole MT ferrule 1 a as an example of part of amulti-fiber connector according to an exemplary embodiment of thepresent invention. Ferrule 1 a includes a body 2 in which a plurality offiber holes 3 are formed therethrough and extend in a longitudinaldirection. Each of the fiber holes 3 is capable of being populated withan optical fiber 5 of a multi-fiber optical cable. In addition, theferrule 1 a includes guide-pin holes 7 formed in the body 2 and whichare aligned with and receive guide-pins of another ferrule, a lightemitting or receiving device.

According to the ferrule 1 a shown in FIG. 1A, only a portion of thefiber holes 3 available are selected to be populated with an opticalfiber 5. In particular, hole #4 and hole #6 from the left are populatedwith optical fibers of the multi-optical cable. The remaining fiberholes are left empty. Accordingly, only another ferrule having amatching configuration of populated fiber holes 3 will be able to form aproper connection with ferrule 1 a of FIG. 1A. In this example, anotherferrule having holes #4 and 6 populated with optical fibers will be ableto form a proper connection with ferrule 1 a. On the other hand, aferrule populated with fibers in holes #1 and 2 will not be able to forma proper connection with ferrule 1 a.

FIG. 1B illustrates a 72-hole MT ferrule 1 b as another example of partof a multi-fiber connector according to an exemplary embodiment of thepresent invention. Ferrule 1 b includes 72 fiber holes 3 arranged in 6rows of 12. Hole #2 from the left in the third row is populated with anoptical fiber of a multi-fiber optical cable. The other 71 holes areleft empty. Thus, only another ferrule that has a fiber populated in thesame manner can form a proper connection with ferrule 1 b.

Accordingly, through predetermined positioning of optical fibers in amulti-position ferrule within a connector, a secured network connectioncan be formed between two mating connectors. This is because two matingconnectors, held together on separate sides of an adapter, will onlyhave physically connecting optical fibers if the fibers on bothconnectors have matching positions. Thus, the information transferthrough the mating pair(s) of optical fibers is secured since anincoming connector to an adapter, that already has a connectors on itsother end, is prevented from making a physical connection between a pairor pairs of optical fibers, unless the positioning of the optical fiberswithin the connectors are matched.

FIG. 2 illustrates a connecting system according to an exemplaryembodiment of the present invention. In particular, FIG. 2 showsmatching fiber positions in a pair of connector plugs, which mate in akey-up-to-key-down configuration. The connecting system includes twocable assemblies 10 terminated with a connector plug 12 on each endsection of an optical cable 14. Each connector plug 12 includes ahousing 16 and a multi-fiber ferrule 1 disposed within the housing 16.The connecting system also includes an adapter 20 which has tworeceptacles 22 on either side, each receptacle 22 receiving one of theconnector plugs 12. Accordingly, a pair of connector plugs 12 are heldtogether by the adapter 20.

As shown in FIG. 2, the positioning of the optical fibers 5 among theplurality of fiber holes 3 in the two connector plugs 12 mirror eachother such that the optical fibers 5 in the two mating connector plugs12 have a corresponding matching position that compliments each other.Because the connector plugs 12 shown in FIG. 2 have a matchingpositioning of optical fibers disposed within ferrules 1, a properconnection between the connector plugs can be achieved when the twoconnector plugs 12 are connected by the adapter 20. Thus, by using apredetermined and distinctive selection of positions among a pluralityof possible fiber hole positions, security in the connecting system canbe ensured.

The number of combinations and permutations achievable by the connectionsystem is dependent on the number of available fiber positions on themulti-fiber ferrule 1 and the number of optical fibers needed for thespecific connecting system.

Accordingly, the need to have different connector housings withdifferent physical barriers to prevent either unauthorized insertion ofa connector plug into the receptacle of an adapter or unauthorizedremoval of a connector plug from an adapter can be eliminated. That is,a common connector housing can be used for all connector plugs. Inaddition, one common adapter may be used to connect the connector plugs.

Identification of connector plugs with specific fiber positioning can becarried out through color-coding the components of the connector plugs,such as plug housings or connector plug boots. Identification ofconnector plugs with specific fiber positioning can also be carried outthrough number coding of the cable assemblies, or other types ofmarking.

FIG. 3 shows matching fiber positions in a pair of connector plugs 12,mating in a key-up-to-key-up configuration according to anotherexemplary embodiment.

FIG. 4 shows two pairs of matching fiber positions in a pair ofconnector plugs 12, mating in a key-up-to-key-down configurationaccording to another exemplary embodiment.

FIG. 5 shows two pairs of matching fiber positions in a pair ofconnector plugs 12, mating in a key-up-to-key-up configuration accordingto another exemplary embodiment.

FIG. 6 shows matching fiber positions in a pair of connector plugs 12with two rows of possible fiber positions, mating in akey-up-to-key-down configuration according to another exemplaryembodiment.

FIG. 7 shows matching fiber positions in a pair of connector plugs 12with two rows of possible fiber positions, mating in a key-up-to-key-upconfiguration according to another exemplary embodiment.

FIG. 8 shows two pairs of matching fiber positions in a pair ofconnector plugs 12, mating in a key-up-to-key-down configurationaccording to another exemplary embodiment.

FIG. 9 shows two pairs of matching fiber positions in a pair ofconnector plugs 12, mating in a key-up-to-key-up configuration accordingto another exemplary embodiment.

Accordingly, the exemplary embodiments uses the plurality of fiber holesfeature of a multi-fiber ferrule to achieve physical security in theconnecting system of a network. By choosing different discrete positionsof a multi-fiber ferrule, proper connection can only be made if themating pair of connectors both have fibers in the position(s) thatcomplement each other.

Although a few exemplary embodiments have been shown and described, itwill be appreciated by those skilled in the art that changes may be madein these exemplary embodiments without departing from the principles andspirit of the invention, the scope of which is defined in the appendedclaims and their equivalents. For example, although the above exemplaryembodiments utilize optical fibers, non-optical fibers could also beused without departing from the principles and spirit of the invention.

What is claimed is:
 1. A multi-fiber connector comprising: amulti-position ferrule including a plurality of fiber holes arranged ina predetermined pattern; and at least one fiber, wherein each of theplurality of fiber holes is configured to receive one of the least onefiber and each fiber is selectively inserted within one of the pluralityof fiber holes at a selected position among the plurality of fiberholes, wherein only a portion of the plurality of fiber holes arepopulated with the at least one fiber and a remaining portion of theplurality of fiber holes are not populated.
 2. The multi-fiber connectorof claim 1, wherein each of the at least one fiber is an optical fiber.3. The multi-fiber connector of claim 1, wherein the at least one fiberincludes only one fiber.
 4. The multi-fiber connector of claim 1,wherein the at least one fiber includes at least two fibers.
 5. Themulti-fiber connector of claim 1, wherein at least one of the pluralityof fiber holes is not populated with the at least one fiber.
 6. Amulti-fiber connector system comprising: a first multi-fiber connectorwhich comprises: a multi-position ferrule including a plurality of fiberholes arranged in a predetermined pattern; and at least one fiber,wherein each of the plurality of fiber holes is configured to receiveone of the at least one fiber and each fiber is selectively insertedwithin one of the plurality of fiber holes at a selected position amongthe plurality of fiber holes, wherein only a portion of the plurality offiber holes are populated with the at least one fiber and a remainingportion of plurality of fiber holes are not populated; and a secondmulti-fiber connector which comprises: a multi-position ferruleincluding a plurality of fiber holes arranged in a predetermined patternhaving matching positions corresponding to the predetermined pattern ofthe first multi-fiber connector; and at least one fiber, wherein each ofthe plurality of fiber holes is configured to receive one of the atleast one fiber and each fiber is selectively inserted within one of theplurality of fiber holes at a selected position among the plurality offiber holes, wherein the plurality of fiber holes are populated with theat least one fiber such that the first multi-fiber connector and thesecond multi-fiber connector have a matching configuration of populatedfiber holes and unpopulated fiber holes.
 7. The multi-fiber connectorsystem of claim 6, wherein each of the at least one fiber is an opticalfiber.
 8. The multi-fiber connector system of claim 6, furthercomprising an adapter configured to receive the first multi-fiberconnector and configured to receive the second multi-fiber connector,wherein the at least one fiber of the first multi-fiber connector andthe at least one fiber of the second multi-fiber connector mate incoaxial alignment to effect an interconnection.
 9. A method ofconnecting multi-fiber connectors in a secure fiber network, the methodcomprising: selecting at least one fiber hole of a plurality of fiberholes of a first multi-fiber connector to populate with a fiber, whereineach of the plurality of fiber holes is configured to receive saidfiber; selecting not to populate at least one fiber hole of theplurality of fiber holes of the first multi-fiber connector with anotherfiber such that only a portion of the plurality of fiber holes of thefirst multi-fiber connector are populated with at least one fiber and aremaining portion of the plurality of fiber holes of the firstmulti-fiber connector are not populated; inserting at least one fiber inonly the selected at least one fiber hole of the first multi-fiberconnector; selecting at least one fiber hole of a plurality of fiberholes of a second multi-fiber connector to populate with another fiber,wherein each of the plurality of fiber holes is configured to receivesaid other fiber; selecting not to populate at least one fiber hole ofthe plurality of fiber holes of the second multi-fiber connector withanother fiber such that only a portion of the plurality of fiber holesof the second multi-fiber connector are populated with another at leastone fiber and a remaining portion of the plurality of fiber holes of thesecond multi-fiber connector are not populated, inserting the another atleast one fiber in only the selected at least one fiber hole of thesecond multi-fiber connector; coupling the first-multi-fiber connectorto an adapter.
 10. The method of connecting multi-fiber connectors in asecure fiber network of claim 9, wherein each of the at least one fiberand each of the another at least one fiber are optical fibers.
 11. Themethod of connecting multi-fiber connectors in a secure fiber network ofclaim 9, the method further comprising: coupling the second multi-fiberconnector to the adapter such that the at least one fiber of the firstmulti-fiber connector and the another at least one fiber of the secondmulti-fiber connector mate in coaxial alignment to effect aninterconnection, wherein the first multi-fiber connector and the secondmulti-fiber connector have a matching configuration of populated fiberholes and unpopulated fiber holes.
 12. The multi-fiber connector ofclaim 1, wherein only one of said fiber holes is populated with a fiber.13. The multi-fiber connector of claim 12, wherein the majority of fiberholes are not populated with fibers.
 14. The multi-fiber connectorsystem of claim 6, wherein only one of said fiber holes in eachconnector is populated with a fiber.
 15. The multi-fiber connector ofclaim 14, wherein the majority of fiber holes in each connector are notpopulated with fibers.
 16. The method of connecting multi-fiberconnectors in a secure fiber network of claim 9, wherein only one ofsaid fiber holes in each connector is populated with a fiber.
 17. Themethod of connecting multi-fiber connectors in a secure fiber network ofclaim 16, wherein the majority of fiber holes in each connector are notpopulated with fibers.